What Causes Air Handler Coils to Freeze?

In a central air conditioner, the air coil absorbs heat from household air that is passed over it by the air handler. This cools the air in your home, while also removing humidity. In certain conditions, the absorption of heat can be reduced, allowing the air coil to cool and ice to form from the moisture that is removed from the air. Once the coil freezes, your air conditioner will not be able to cool properly, and it may stop working completely to protect the compressor from damage.

Causes of a Frozen Air Coil

There are several conditions that can cause the air coil to freeze, including:

  • A clogged air filter – When the air filter is clogged, the amount of air flowing over the air coil is reduced, preventing proper heat absorption and allowing the coil to freeze.
  • Duct obstructions – A blockage in a duct can also reduce airflow and freeze the coil. This can include debris falling into a floor vent, damaged ducts, clogged ducts, or closed vents in one or more rooms. Obstructions in either the return or supply ducts can cause problems, because an air conditioning system requires balanced airflow to work properly.
  • Fan problems – If the blower motor, blower fan, or belt is damaged, the amount of air flowing over the coil can be reduced, allowing it to freeze.
  • Dirty coils – Dirt and debris on the air coil can prevent heat absorption, allowing the coil to freeze.
  • Low refrigerant – If there is not enough refrigerant in the system, the air conditioner will not be able to absorb heat properly and the coil can freeze.

If your air coil freezes, you should shut the air conditioning system off by raising the temperature on the thermostat. Allow the air coil to thaw naturally, and do not use any tools, like scrapers, to remove the ice, as they could puncture the coils. Clean or replace your air filter if it is excessively dirty or clogged, and check all the vents in your home to make sure they are not closed or blocked by furniture, drapes, or other objects.

Restart the system once the coil has thawed completely, and if it freezes again, it is a good idea to have the system professionally inspected.

Air Conditioning Services in Baltimore and Annapolis, MD

If your air coil continues to freeze, contact our team at All Seasons Heating & Cooling for fast, professional service. Whether your air coil is dirty, you have a refrigerant leak, or your blower motor has failed, our NATE certified HVAC experts can find the problem quickly and offer reliable, cost-effective repairs. We serve homeowners and businesses throughout the Baltimore and Annapolis areas, and with over 50 years of combined HVAC experience, you can be sure the job is done properly the first time!

Contact All Seasons Heating & Cooling today at (443) 304-2379 for air coil repairs and service in Baltimore or Annapolis!

Request Service
With All Seasons Today!
Heating System Inspection
Got Allergies?
If you're coughing,
sneezing, or have allergies, click here for our solution!
Winter, Spring, Summer, Fall - One Call Does It All!
CALL ALL SEASONS (443) 304-2379